The present invention relates to an information storage medium and an apparatus for reproducing information from the information storage medium, and more particularly to an information storage medium suitable for storing musical accompaniments, so-called "karaoke", and an apparatus for reproducing information from the information storage medium.
A conventional apparatus for playing back pre-recorded musical accompaniments, or a musical accompaniment playback apparatus, reproduces such pre-recorded musical accompaniments by playing back information recording mediums, such as magnetic tapes, video disks, etc., on which only musical accompaniments are recorded. Such a musical accompaniment playback apparatus includes an amplifier connected to a microphone and a loudspeaker, and mixes vocal signals supplied from the microphone with signals of reproduced musical accompaniments, amplifies the mixed signals, and supplies the amplified signals to the loudspeaker to produce audible sounds.
When a user of the musical accompaniment playback apparatus wants to sing a desired song recorded in an information storage medium such as a magnetic tape, a disk, or the like, it is necessary for the user to look for the registered number of the information storage medium and the registered number of the desired music piece in a printed list of music pieces or music titles, to select the information storage medium which stores the desired music piece, load the selected information storage medium into the musical accompaniment apparatus, and select the desired music piece according to the registered number thereof.
Some users may be desirous of using the musical accompaniment playback apparatus in passenger cars. It would be convenient if a desired music piece can be selected even without a list of music titles.
Recently, compact disks (CDs), which are one type of digital audio disks, are used as a recording medium for karaoke music or musical accompaniments. On a CD, pulse-code-modulated musical information is recorded in time-divided storage areas. Code information, referred to as a "subcode", is recorded at the leading end of each of the storage areas. One of the innovative features of the CDs is that any desired music piece recorded on a CD can quickly be selected or accessed by searching the subcodes on the CD at high speed. One storage area, known as "TOC" (Table of Contents) and serving as a table of subcodes for retrieving recorded music pieces, is located on the innermost track of the CD, called "lead-in area", which is read first at the playback. The TOC storage area has a storage capacity of 9 bytes. When a CD is loaded in a CD player, the CD Player reads the data of the TOC on the CD. The user inputs a control command indicative of the subcode corresponding to the leading end of a desired music piece recorded on the CD. Then, the CD player searches for an address having the indicated subcode on the CD, and moves an optical pickup to a radial position on the CD which corresponds to the address. When the optical pickup reaches the addressed position, it starts to reproduce the music information from the address.
The TOC storage area stores code information, rather than music titles, because of the limited storage capacity. Therefore, in order to selectively play back a desired music piece, the user needs a printed list of music titles and code information related to the music titles.